改进人工势场的手术机器人位姿规划  

Pose planning for surgical robot with improved artificial potential field method

作　　者：郝林佳 叶灿 都书鲜 王宇[1,2] 武博[1,2] 张楠[1,2] HAO Lin-jia;YE Can;DU Shu-xian;WANG Yu;WU Bo;ZHANG Nan(School of Biomedical Engineering,Capital Medical University,Beijing 100069,China;Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application,Capital Medical University,Beijing 100069,China)

机构地区：[1]首都医科大学生物医学工程学院,北京100069 [2]首都医科大学临床生物力学应用基础研究北京市重点实验室,北京100069

出　　处：《控制理论与应用》2022年第6期1121-1129,共9页Control Theory & Applications

基　　金：国家自然科学基金项目(61672362);北京市自然科学基金项目(4172012)资助。

摘　　要：运动避障与路径规划是手术机器人自动化手术中重要的技术环节,为机器人手术提供了良好的术中安全性及准确性.本研究针对上述两关键技术,提出改进人工势场的手术机器人位姿规划算法,首先,通过对引力函数进行改进,在不求取运动学逆解的情况下,能够准确驱动机械臂到达指定位姿;接着,利用快速凸包算法将障碍物凸体化,通过Gilbert Johnson Keerthi(GJK)算法计算障碍物与机械臂连杆等效圆柱面之间的最近距离,使避障距离更加准确;然后,通过自适应步长,使机械臂运动更加平稳快速;最后,引入动态引力常数,使机械臂具有逃离局部极小值的能力.实验结果表明,本研究能够让机器人在避障情况下平稳快速到达规划位姿,并在陷入局部极小值时逃逸,为未来医疗机器人在自动化手术方面提供了新思路.Motion obstacle avoidance and path planning are very important technical links in automated surgery of surgical robots,which provide good intraoperative safety and accuracy for robotic surgery.Aiming at the above two key technologies,a pose planning algorithm of surgical robot with improved artificial potential field is proposed.Firstly,by improving the gravitational function,the robot can be accurately driven to the specified pose without obtaining the inverse kinematics solution.Secondly,the fast convex hull algorithm is used to make the obstacle convexification,and the closest distance between the obstacle and the equivalent cylindrical surface of the links are calculated by the Gilbert Johnson Keerthi(GJK)algorithm,so that the obstacle avoidance distance is more accurate.Thirdly,the adaptive step size is adopted to make the movement of the robot more stable and faster.Finally,a dynamic gravitational constant is proposed to enable the robot to escape from the local minimum.The experimental results show that the research can make the robot smoothly and quickly reach the planned pose while avoiding obstacles,and escape when falling into the local minimum,which provides new ideas for future medical robots in automated surgery.

关 键 词：避障 路径规划 手术机器人 人工势场 自适应步长 局部极小值 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置] R318.6[自动化与计算机技术—控制科学与工程]